Oil-burning apparatus



A rirm, 1924. 1,492,135

N. E. LEWIS ET AL OIL BURNING APPARATUS Filed March 30. 1922 ATTORNEYY NATHAN E. LEWIS. OF PLAINFIELD, AND THOMAS IB. STILLMAN, 0F HOBOKEN, NEW" JERSEY, ASSIGNORS TO THE BABCOCK & WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

OIL-BURNING- APPARATUS.

Application filed March 30, 1922. Serial No. 548,019.

To all whom it may concern:

Be it known that we, NATHAN E. LEWIS and Tnoams B. STILLMAN, citizens of the United States. residing at Plainfield, in the county of Union and State of New Jersey, and at Hoboken, in the county of Hudson and State of New Jersey, respectively, have invented certain new and useful Improvements in Oil-Burning Apparatus, of which the following is a specification.

Our present invention relates to oil-burning apparatus, and particularly devices by which air may be supplied to oil burners used in connection with furnaces so that, in the event of accident, the resultant efiects will be minimized.

lVith this and other objects in view, our invention consists of the constructions and arrangements hereinafter described and more specifically pointed out in the appended claim. I

In the drawings, Fig. 1 is a vertical section of an illustrative form of one embodiment of our invention taken on the lines 1-1 of Figs. 2 and 3;Fig. 2 is a front elevation of the arrangement shown in Fig. 1; Fig. 3 is a section on the line 33 of Fig. 1; Fig. at is a fragmentary view similar to Fig. 3, but with the parts in different positions, and Figs. 5 and 6 are respectively plan and elevation of the form of flap valve shown in the illustrative embodiment.

Similar reference characters refer to similar parts in the several views.

In the drawings, we have selected, for purposes of illustration, an arrangement similar to that shown in the patent to Peabody and Stillman No. 1,261,281, granted April 2, 1918. Referring to the arrangement shown in Figs. 1 to 6, inclusive, 10 is a furnace wall having an opening 11. In front of the opening 11 and attached to the wall 10 is a mixing chamber 12 having a plurality of blades 13. Attached to the mixing chamber 12 is a casing 14 in which is sup orted a burner 15. In the form illustrate the burner 15 is in the center of the casing 14.- which is circular in form.

In the periphery of the casing 14 are a number of air inlet openings 16 and mounted on horizontal pivots 17 are flap valves 18, a flap valve being provided for each of the openings 16. The pivot for each flap valve is at one side of the center of the flap so that the area on one side of the pivot is larger than on the other.

Each of the flap valves is free to turn on its pivot and is counterbalanced so that the larger end has a relatively slight tendency to hold the valve open normally. This counterbalancing may be done in the proportioning of the parts of the flap or by the attachment. of counterweights 19, according to the relative position of the flap valves.

Each of the flap valves is provided, in the illustrated form, with a toe piece 20 arranged to engage the curved arms 21 of a spider controlled by a handle 22. These curved arms, when cooperating with the toes 20. limit the amount of opening of the flap valve and therefore of the amount of air which will pass through the opening 16 to the casing 14 and from thence to the mixing chamber 12.

The arrangement shown in Figs. 1 to 6 is for natural draft, and since the area of the flap on one side of the pivot is larger than on the other, it will be seen that the'valves will be held open even when the flaps are substantially in equilibrium around the pivot 17. In other words, the force holding the flap valves open is very slight.

It sometimes occurs that, by reason of an accident to the apparatus with which the burner is connected, the internal pressure in the furnace, as from an explosion, the opening of a water tube of a boiler or the like, will cause air and gases to blow back through the mixing chamber 13 and attempt to flow out of the openings 16. This would carry flame into the operating room and might cause serious disaster. Our present arrangement is intended to prevent or minimize the effects of such an accident. As soon as the gases flow from the furnace so as to create a back pressure, the flaps 18 will be closed and, by reason of the substantial equilibrium of the parts around the pivot 17, this closing will occur instantly before the back pressure has donemuch more than neutralize the natural inward draft through the openings 16. The closing of the valve 18 will prevent the passage of flame into the operating room.

By utilizing gravity alone to balance the valves 18, we secure an arrangement which will respond instantly under all conditions to the slightest amount of back pressure,

' the valves may which would not be true if springs or the like were used for this purpose. It will be understood that during the operation of the burner,

be set so that they are relatively wide open, in which case, the springs, if such were used, would have to exert enough pressure to hold the-valves in this wide open position. The pressure of these springs would be increased as the valves were moved to half-closed or normallyclosed position, so that a considerable increase in back pressure would be necessary before the valves would close. By utilizing gravity, the pressure to be overcome by the back pressure will be constant, regardless of the position in which the flap valves are set. Moreover, the heat to which the springs may be subjected causes them to deteriorate which, of course, is not true of the weights which we use.

When the oil burner of the apparatus illustrated is shut down, it sometimes happens that the flow of oil is not entirely closed ofi by the operation. Oil will then drip from the end of the burner 15 into the lower part of the casing 14: between the mixing chamber 13 and the openings 16. Fuel oil is heavy and sticky and if it acinlet openings at the rear cumulates on one of the valves 18, and particularly on its pivots, will clog it up so as to render it inoperative. We avoid this difficulty by positioning the openings 16 so that one of them will come at the bottom of the casing 14, and we locate the pivots for the corresponding flap valve 18 so that they are removed from the lower part of the casing. Hence, the oil which enters the casing may flow out without contact with the valve 18 cooperating with that opening and particularly without contact with the pivots of that valve. This arrangement is best shown in Fig. 3.

We claim In an oil-burning apparatus, a horizontal oil spraying tube, a casing surrounding the tube and provided with a plurality of air of the outlet end of the tube, and a flap valve for each of said openings,- located in the casing so that some part of the opening is in the lowest part of the easing and the pivots of the valve cooperating with said opening being located above the lowermost part of the casing.

NATHAN E. LEWIS. THOMAS B. STILLMAN.

one of the openings being 

